Explore topic-wise MCQs in Computational Fluid Dynamics.

This section includes 10 Mcqs, each offering curated multiple-choice questions to sharpen your Computational Fluid Dynamics knowledge and support exam preparation. Choose a topic below to get started.

1.

The value of y+ at the intersection between the linear profile and log-law is ___________

A. 20
B. 5
C. 30
D. 11.63
Answer» E.
2.

The value of y+ is 50. Which layer does it belong to?

A. Inertia dominated layer
B. Velocity defect layer
C. Log-law layer
D. Law of the wake layer
Answer» D. Law of the wake layer
3.

What is the range of y+ in the buffer layer?

A. 0 &lt; y<sup>+</sup> &lt; 5
B. 5 &lt; y<sup>+</sup> &lt; 30
C. 30 &lt; y<sup>+</sup> &lt; 500
D. 10 &lt; y<sup>+</sup> &lt; 20
Answer» C. 30 &lt; y<sup>+</sup> &lt; 500
4.

Wall function cannot be used when ___________

A. y<sup>+</sup>&lt;30
B. y<sup>+</sup>&gt;30
C. y<sup>+</sup>&lt;20
D. y<sup>+</sup>&gt;20
Answer» B. y<sup>+</sup>&gt;30
5.

What is the unit of y+?

A. y<sup>+</sup> is dimensionless
B. m
C. m<sup>2</sup>
D. 1 m
Answer» B. m
6.

What is shear velocity?

A. Square of the ratio of density to wall shear stress
B. Square root of the ratio of density to wall shear stress
C. Square of the ratio of wall shear stress to density
D. Square root of the ratio of wall shear stress to density
Answer» E.
7.

Let y be the distance from the wall, ut be the shear velocity and be the kinematic viscosity. Which of these equations define y+?

A. y<sup>+</sup>=y/u<sub>t</sub>
B. y<sup>+</sup>=u<sub>t</sub> /y
C. y<sup>+</sup>=(y u<sub>t</sub>)/
D. y<sup>+</sup>=u<sub>t</sub>/y
Answer» D. y<sup>+</sup>=u<sub>t</sub>/y
8.

The concept of y+ is not used in which of these laws?

A. Law of the wall
B. Law of the wake
C. Log law
D. Linear law
Answer» C. Log law
9.

The value of y+ is used while finding ___________

A. eddy kinematic viscosity for the turbulent boundary layers
B. mixing length for the turbulent boundary layers
C. eddy dynamic viscosity for the turbulent boundary layers
D. kinetic energy for the turbulent boundary layers
Answer» C. eddy dynamic viscosity for the turbulent boundary layers
10.

The value y+ is important only when we deal with ___________

A. turbulent boundary layers
B. turbulent jets
C. free turbulent mixing layers
D. turbulent wakes
Answer» B. turbulent jets